The emergence of 10G Ethernet network interface cards gives network professionals a new tool for getting more bandwidth to servers, but industry observers say some users might find better value for scaling server pipes by installing multi-port Gigabit NICs.

Until 10G prices come down - and they are expected to - users can save almost 80% by buying multi-port Gigabit cards instead of a single 10G Ethernet card, if bandwidth needs don't exceed 4G bit/sec. High-volume Web/intranet or database servers could be good candidates here, experts say.

But for companies looking for a NIC to move large blocks of data on and off servers - such as network-attached storage devices - 10G NICs might be more versatile.

Intel was the first to market a 10G Ethernet network controller in 2002, and other vendors such as S2IO and Chelsio Communications have since debuted 10G NIC products. These products promise network speeds as high as 5G to 7G bit/sec per connection - because of limitations in operating system software and PCI-X bus speeds - and can be trunked to bring Gigabit speeds in the double digits to some high-end boxes.

The multi-port benefit

But some observers say if a need exists for a 2G to 4G connection, users would be better served by installing multi-port Gigabit cards. These cards offer as many as four 1000Base-T ports on one PCI-X card and can be trunked to create a virtual 4G pipe.

With the cost of 10G NICs in the $2,000 to $5,000 range, multi-port NICs offer a lower price-per-Gigabit cost, with prices about $400 per card.

Made by such vendors as Intel and Syskonnect, four-port NICs also typically run on copper wiring, which is less expensive to install than fiber cabling - a requirement to run 10G Ethernet. More importantly, quad-port NICs don't need a 10G Ethernet port on the other end, as prices for 10GBase-LX switch ports are still in the $7,000 to $8,000 range.

"If you need to go above one Gigabit" on a server connection right now, "it's more cost-effective to go with a multi-port Gigabit card vs. a 10 Gigabit" NIC, says David Newman, president of Network Test, a network equipment testing firm, and a member of the Network World Lab Alliance.

Besides the cost of the equipment, Newman says other factors involved with running a data center play into the decision of whether to go multi-port Gigabit or single-port 10 Gigabit.